Originally Posted by
fumje
Usually the sequence of events is (i) they cancel the flight, automatically rebook something else, and leave a schedule change notice on the reservation; (ii) if the computer got confused and failed to rebook, it will leave the reservation in limbo (possibly showing only PHX-EWR) until you call them or; (iii) they call you any time before T-24h to ask what you want to do.
If the EWR-MAN flight is not officially cancelled yet, nothing for you to do but wait.
The routing has changed 4 times since I made my original post and as of last night, the EWR-MAN leg has disappeared altogether (as per ii above). I suspect that the next alteration (maybe tonight/tomorrow) will show a routing via Germany.
Plenty of time to go !